Online Virus / Malware News

[October 5 update at end of file]

The Storm worm marked its presence in early 2007 and became an infamous robot network primarily known for its spamming and phishing activities. Also known as Nuwar/Zhelatin/FakeAV/Peacomm, this bot reappeared early this year, distributed by fake AV software and Trojan downloaders. Storm is a major botnet when compared with many other spamming bots, due to the massive volumes of spam it sends from the victim’s machine. It also uses a fast-flux mechanism to hide its distribution areas. During our static analysis of the Storm executable, we observed it to be heavily obfuscated with an unknown packer and an infinite loop to halt its activity whenever it detects a debugging or virtual machine environment.

Storm’s spam campaign activity includes a variety of spam, with most related to online pharmacy scams and adult products. To get around, this botnet also includes malicious links to URLs that exploit several client vulnerabilities.

Our analysis of Storm confirmed and uncovered some of its unique characteristics, which help network intrusion prevention systems to implement reliable detection mechanisms for Storm’s control activity.

Static Analysis of the Storm Worm
We looked inside the variant we received in April 2010. In the initial part, this sample has various decryption routines. This binary starts with moving 0×5090 bytes to the heap and thereafter executing decryption routines to unpack the binary in stages.

After a complete execution of the loop, the binary is moved to the heap section and then decrypted:

This executable then copies itself as asam.exe into c:\windows, modifies the registry key to execute at Windows start-up, creates the process
asam.exe, and terminates itself.

Analysis of the HTTP Communications Code Within the Dropped File asam.exe

We reverse-engineered this Storm file and came across some of the unique characteristics of its control channel, which is based on base64-encoded, gzipped HTTP data. The code snippets below reveal our analysis of its HTTP communications.

URI Extensions in the POST Request
Hard-coded URI extensions and the URI length that is used in the POST request initiated by Storm:

Random Generation Functions to Form the URI Request Path

The next code snapshot shows the random character-generation function that generates 3 bytes of random alphabetical characters which are appended with the “.” to form the request URI path. Thereafter, the random generation function is called again to select any random extension from .jpg, .htm, and .gif, and completes the URI formation by appending it to the previously generated request path:

HTTP POST Request Header

These are the low-level details of how the POST request will look when the worm is executed on the machine:

As we figured out from the code above, this variant communicates with the bot master via an HTTP POST request. In examining the POST request code, another clue is the possible typo in the user-agent header, in which it is set to “Mozilla/4.0 (compatible; MSIE 6.0; Windoss NT 5.1; SV1).” (Note “Windoss” instead of Windows. This is a very good hint that Storm is in action; intrusion prevention systems can use this hint to detect Storm on the wire.) The botnet server then responds with the spam template used by the bot to send the spam.

All the preceding data from the server is base64 encoded. After decoding the response from the server, we found following spam template:

Once the bot client decodes this data, it uses the following looped SMTP engine code to send spam mails based on the spam template.

Let’s take a look at one of the spam mails generated by this bot:

More Uncovered Commands

Early variants of this bot had different components and separate binaries for carrying out specific commands; yet the one we analyzed seems to have all the control code embedded inside the single component. As seen in the code below, we found the downloader component, which downloads additional malware onto the system, and the updater component, which downloads the latest copy of the bot executable. Once any of these commands are detected in the server response, the bot allocates the heap to store the received data.

Scanning the Drive for Files
Storm also includes a routine to scan the drives for files with the following extensions:

.wab, .txt, .msg, .htm, .shtm, .stm, .xml, .dbx, .mbx, .mdx, .eml, .nch, .mmf, .ods, .cfg, .asp, .php, .pl, .wsh, .adb, .tbb, .sht, .xls, .oft, .win, .cgi, .mht, .dhtm, .jsp, .dat, .lst

It also searches for particular strings within these files, probably to extract the information about the host and email addresses contained in them:

@microsoft, rating@, f-secur, news, update, anyone@, bugs@, contract@, feste, gold-certs@, help@, info@, nobody@, noone@, kasp, admin, icrosoft, support, ntivi, unix, bsd, linux, listserv, certific, sopho, @foo, @iana, free -av, @messagelab, winzip, google, winrar, samples, abuse, panda, cafee, spam, pgp, @avp., noreply, local, root@, postmaster@

Detecting Storm Worm on the Wire
The majority of mail traffic over the Internet is spam. We need to detect these spam bots and try to keep them from proliferating. Our analysis provides good hints for detecting Storm traffic on the network. One high-confidence approach would be to correlate multiple suspicious events happening on the network within a short time. One example is a user-agent check for the typo we saw; we can correlate this with the multiple outbound DNS MX queries from the same source within a short time. An even more reliable detection would be to correlate those two events with a spontaneous increase in the outbound SMTP connections from the source. By following up on these hints we can increase our ability to detect Storm at the network gateway.

Update:
McAfee IPS Coverage Status
McAfee Intrusion Prevention (formerly IntruShield) has released coverage for the Storm bot under the attack ID 0×48804200 BOT: Storm Bot Activity Detected. McAfee customers with up-to-date installations are protected against this malware.

During the last six years, botnets have become one of the biggest threats to security professionals, businesses, and consumers. We at McAfee Labs have just released more information about how cybercriminals can use common social networks and common web applications, such as Twitter and XMPP-enabled applications like Google Talk, to take over a user’s computer.

As Web 2.0 services evolve, so do the efforts of botnet writers. They are rapidly adopting new technologies to increase the sophistication of their attacks. We have identified the following trends in botnets and social media:

• Twitter-controlled bots are the most prevalent example of using social media to receive and execute bot commands
• KreiosC2, though a proof-of-concept research tool, effectively demonstrates how LinkedIn and other social networks and applications can be used to control a botnet
• Protocol standards such as XMPP, used for authentication, presence, and messaging, can also be used by cybercriminals to communicate with botnets and execute malicious attacks

The dangers from controlling a bot or botnet through an application such as Twitter cannot be understated. Using widely adopted and deployed applications like Twitter to control a botnet effectively allows the attacker to hide in plain site by using an application or website that is allowed on most desktops worldwide. There’s nothing to it: Log into a Twitter account from a variety of Twitter applications (I’ll use TwitScoop) and send an update:

Then we send our command:

It really is as simple as that: decentralized, application-based control of one or many bots. Don’t try this at home: I ran this exercise from a private Twitter account with only one follower (my other Twitter account) in a research environment, so there was no danger!

The McAfee Labs research team has released a report that examines TwitterBots, KreiosC2, and XMPP as examples of how cybercriminals can use social networks as the new platform for botnet command, control, and attack.

During the last six years, botnets have become one of the biggest threats to security professionals, businesses and consumers. We at McAfee Labs have just released more information about how cybercriminals can use common social networks and common web applications, such as Twitter and XMPP-enabled applications like Google Talk to take over a user’s computer.

As Web 2.0 services evolve, so do the efforts of botnet writers. They are rapidly adopting new technologies to increase the sophistication of their attacks. We have identified the following trends in relation to botnets and social media:

-Twitter controlled bots are the most prevalent example of using social media to receive and execute bot commands
-KreiosC2, though a proof-of concept research tool, effectively demonstrates how LinkedIn and other social networks and applications can be used to control a botnet
-Protocol standards like XMPP, used for authentication, presence and messaging, can also be used by cybercriminals to communicate with botnets and execute malicious attacks

The danger’s from controlling a bot or botnet through an application like Twitter cannot be understated. Using WIDELY adopted and deployed applications like Twitter to control a botnet effectively allows the attacker to hide in plain site by using an application or website that is allowed on most desktops worldwide. It is as simple as logging into one’s Twitter account from a variety of Twitter applications (I’ll use TwitScoop) and sending an update:

Then we send our command…..

It really is as simple as that – decentralized, application-based control of one or many bots. BTW – This was done from a private Twitter account with only 1 follower (my other Twitter account) in a research environment so there was no danger!

Our research team has released a whitepaper that examines TwitterBots, KreiosC2 and XMPP as examples of how cybercriminals can use social networks as the new platform for botnet command, control and attack.

McAfee Labs has been monitoring a spam run that was launched earlier today. The message follows:

The attachments are all the same and contain an encoded JavaScript, which redirects to a web page on the numerouno-india.com domain.

The destination page does a redirect (to a page on the scaner-g.cz.cc domain) and also contains an iframe (with a target of a page on the arestyute.com domain).

The redirect domain displays the standard fake anti-virus scanning animated image and subsequent prompt to download an executable:

fake scanning image

download prompt

icon used by executable

The iframe leads to a cocktail of exploits, including a Java Development Toolkit exploit (CVE-2010-0886), as well as exploits targeting Adobe Flash and PDF vulnerabilities, including CVE-2007-5659, CVE-2008-2992, CVE-2010-0188.

The payload of these exploits is a password-stealing Trojan, which copies itself using a randomly named folder and file in the %AppData% directory and creates a registry run key to load the file at start-up, for example:

• HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
  “{608F1285-57B7-C631-DE51-8A99508CC7A9}” = “C:\Documents and Settings\Administrator\Application Data\Ezudi\oqek.exe”

This password stealer injects into the iexplorer.exe process and targets dozens of mainstream financial institutions.  It also contacts the domains ohmaebahsh.ru and eexiziedai.ru.

• This fake AV executable was detected by Global Threat Intelligence File Reputation at the time of this blogging when running at Very Low sensitivity or higher.
• The first-stage domain (numerouno-india.com) is rated RED by TrustedSource and SiteAdvisor
• The second-stage domains (arestyute.com, and scaner-g.cz.cc) are rated RED by TrustedSource and SiteAdvisor
• The third-stage domains (ohmaebahsh.ru and eexiziedai.ru) have been rated RED by TrustedSouce and SiteAdvisor for weeks
• DAT file coverage is being added under the following names:
  • PWS-Zbot
  • FakeAlert-PE
  • JS/Downloader.gen
  • JS/FakeAlert-AB.dldr

Customers may download updated signatures using the extra.dat request page: https://www.webimmune.net/extra/getextra.aspx. These are also available in the beta DATs.

A new phishing scam is targeting users of the Electronic Federal Tax Payment System (EFTPS), a free service provided by the U.S. Department of the Treasury since 1996. The recent fraudulent format uses an email message that claims to be a rejected tax payment and directs users to a fake website for additional information. Remember, don’t ever provide any personal or financial information to unsolicited email messages.

Our research found a set of these fraudulent websites created on September 12. All the URLs are associated with the same IP address and in the same country.

The scam message:
Subject:
Your EFTPS Tax Payment ID has been rejected.

Body:
Report ID: ***. Your Federal Tax Payment ID: *** has been rejected. Return Reason Code R## – The identification number used in the Company Identification Field is not valid. Please, check the information and refer to Code R##  to get details about your company payment in transaction contacts section: http://www.eftps*******7.com/contacts

If you receive one of these messages claiming to be from the EFTPS or IRS, don’t open it or click any link. It’s safer to manually type the URL (web address) instead of clicking a link. To verify whether a government or financial institution is trying to contact you, call that agency. You’ll find useful tips for avoiding phishing scams in this McAfee publication.

Over the weekend I had the chance to put some work into my lowbie dwarf paladin named Boulderbrain. I was at the Stormwind bank minding my own business when I suddenly get this whisper:

Now normally I simply ignore most whispers I get in-game (other times I simply don’t notice them) but this one caught my attention. Zooming in I think you will see why:

This message is telling me that Blizzard suspects my account of using third-party tools to cheat and would I go to their website, login, and check my account settings. In actuality this is an “attacker” pretending to be a Blizzard GameMaster, and the website itself is a phishing site:

This particular fake was hosted on an IP address that had a pretty questionable report. (HINT, HINT use our SiteAdvisor browser plug in!) World of Warcraft has millions of users worldwide, making attacks and techniques like this very common. Many players (myself included) have taken the additional step of using two-factor authentication (commonly called 2FA or simply tokens), which can add an additional layer of protection to your logon credentials:

The addition of the 2FA pin makes it extremely difficult to break into or pop the account itself. (It’s like adding a secondary token to your bank logon.) OK, now granted I got the free Core Hound pup with it, but it also has a sweet iPhone app that generates the 2FA code!

Now what were those third-party apps the original phish may have alluded to? Bots most likely. As anyone who follows this blog is aware, bots refer to robots, usually malicious in nature, but they simply automate tasks. Some of the more popular bots for World of Warcraft are farming and leveling bots. They are designed for pretty much what you would guess: They automate the “farming” of a variety of materials (later sold for in-game gold) or even honor (honor points can be used to purchase in-game items). These bots can also automate the process of leveling your character. Some examples:

and also:

Should your account be found to be using any of these, it will get banned–as it violates Blizzard’s terms of service. Credential and logon theft is one of the biggest areas of malware we at McAfee Labs deal with on a daily basis. Make sure you stay updated, properly configured and be cautious of in-game messages!

And level-up old school–the account you save may be your own!

Social engineering is probably the most common technique for to enticing unsuspecting victims to reveal information or purchase something of no value. In the anti-virus world we often see malware authors use scare tactics to sell rogue anti-virus or “fake alert” anti-virus software.

Rogue malware authors use various methods to fool victims into purchasing their products. Some of the most common methods:

• Creating links to malicious web pages in which common search terms in search engines bring these pages to the top of the list, a.k.a. search poisoning
• Disguising themselves as legitimate applications, especially under peer-to-peer and IRC networks
• Offering downloads as legitimate software using bit torrent protocol

Over the last couple of days McAfee Labs has seen an increase in submissions from customers with regards to one variant of the fake alert family classified as FakeAlert-SpyPro.gen.ai. We’ll describe the characteristic behavior of this variant in this blog. We also have a comprehensive description of this malware in our Virus Information Library.

Once this malware is run on the local machine, it displays a warning indicating that the computer is infected with various types of malware and that the user needs to click to clean the computer.

When the user clicks the warning, it pops up a window and initiates a fake scan on the computer. It shows a number of detections and warns the user that the system is infected. To “clean” the malware from the computer, users must purchase the software from the website “antiv[removed].com”

If left to run, this software attempts to use Internet Explorer to open websites with pornographic content.

The fake alert software also makes a number of changes to the Windows registry so that it can load itself at startup and disables phishing filters on Internet Explorer.
When users attempt to run a legitimate executable, this malware pops up and informs them that the file is infected and if users want to run the anti-virus software to clean the infection.

Here are a few cleaning and remediation steps you can take to remove or keep this malware at bay:

• Ensure that you have a legitimate copy of anti-virus software installed on the machine
• Ensure that software is updated regularly
• Exercise caution when you click on links. Using software such as SiteAdvisor (www.siteadvisor.com) can help because it distinguishes between safe and risky sites.
• Do not be enticed into downloading legitimate software for free, especially from P2P, IRC, or bit torrent networks
• Exercise caution while clicking links in emails that look suspicious, even If they appear to come from a known contact

Two weeks ago, I posted a blog entry talking about the counterfeiting of legal documents. I have received many comments and requests for further data related to this type of fraud from various Eastern Europe countries, France, and even the United States. Aside from journalists, for whom it is their job, many people have contacted or attempted to contact me. Most of them were curious and friendly, but others flooded my mailbox:

The first request was for the URLs of the websites that provide the services. At McAfee, like at most of our competitors, we almost never disclose dangerous URLs apart from researchers in the business and law enforcement agencies. And in many cases we also employ some internal testing to avoid infection or compromise. When I wrote my blog entry, that URL was safe (no malware, no iframe), but this can change, especially if their owners know it will be visited by many inquisitive people.

The next question was that of the counterfeiters nationalities. No doubt they are Russian speakers.

Another request was related to the abundance of these offers. The site I visited actually contained a competitor blacklist with a dozen or so “disreputable” companies. As they were all restricted to drivers licenses, I carried on further investigations on the passport field. It was not difficult to find other offers with more attractive prices: less than US$1,000 instead of the US$4,000-$5,000 asked by the first one.

In this last offer, I noted the availability of diplomatic passports (price on demand).

If you are not a Google search ninja, you can just check YouTube. There, various well-phrased searches can direct you to the online shop you are looking for:

And regarding the payment methods? It seems they all prefer Western Union, but they are not very talkative on this subject. You have first to contact them via anonymous mailing services. (They specify: “no ICQ, no SMS, no phone call.”) However, I discovered another offer, with details about how to place an order.

At last, some people wished to know if these sites offered other materials or services. Some of them sell carding equipment to read/write magnetic cards, but the prices were exorbitant. They quoted between US$9,000 and $11,000; yet many of these devices can be found on Amazon or eBay for $500! Proving the relevance of our previous advice regarding what you toss into your household trash, one site offers fake French EDF (national electricity company) and British Telecom utility bills for £10. (In Europe, we frequently use these documents to prove our residency or proof of address.)

Even the envelope is supplied! Seemingly unimportant pieces of paper can interest today’s cybercriminals.

Yesterday we discovered a new Zeus campaign.

Most of the messages associated with the new spam campaign are linked to the Asprox botnet. This time, the focus is on FedEx. Most of the attachments start with either FedExDoc[randomnumbers].exe or FedExInvoice[randomnumbers].exe. Those attachments are recognized as the Bredolab Trojan, which will download the Zeus component.

This Zeus variant has a control host on hxxp://x5vsm5.ru, but also downloads from hxxp://trachsel.biz.

The targets of these samples are a large number of banks outside the United States. We still see common U.S. targets…

• Citibank
• Comerica
• USBank
• WellsFargo

and also some banks from Europe, the Middle East, Asia, and South America…

• Neue Bank (Liechtenstein)
• Arab Bank
• MyBank (Taiwan)
• BHI Bank (United Kingdom)
• NPBS (United Kingdom)
• Banco de Sabadell (Spain)

as well as several other banks.

Watch out for Zeus’ going global.

The Anti-Malware engine is a critical and core piece of the McAfee anti-malware solutions. As with any core technology, the engine must be rock-solid stable, fast, and functionally rich.

A new McAfee Labs whitepaper outlines these engine technologies and values, covering both endpoint and gateway uses. Beyond introductions to malware detection methodologies–ranging from exact detection to heuristics, and technologies from exploit detection to cloud-based detection, the new paper especially outlines McAfee’s approach to Cooperative Anti-Malware on Endpoint and Gateway. “Cooperative” in this case refers to the added value of combining anti-malware on the endpoint and on the gateway: a true defense-in-depth strategy in action.

In this defense-in-depth implementation we have engine technologies that are optimized for the endpoint and the gateway, respectively, and both are connected through our Global Threat Intelligence back-end, or “cloud.” This combination allows strict enforcement and the highest proactive catch rates at the network perimeter, keeping the majority of threats outside of your network, and effectively and accurately protecting the desktops in an enterprise as well.

Download and read it now!